Oil system

ABSTRACT

The invention relates to an improved system for supplying filtered oil to wet brakes of the tractor without additional/auxiliary pump. The system comprises of a suitably sized connection provided on the drain line of the Hydraulic system, which supplies required quantity of filtered oil to the wet brakes through a passage with a line pressure of 2-3 kg/cm2. This positively ensures the oil supply and circulation of oil for heat removal from wet brakes. A hollow bush is so sized and located on the brake housing so as to maintain the required level of oil in the brake housing and to drain the excess oil in the transmission housing.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to an improved oil system for supply of oil to wet brakes of a tractor without the requirement of an additional auxiliary oil pump.

[0003] 2. Background of the Related Art

[0004] It is generally known that oil supply systems for wet brakes utilize assemblies that employ either an auxiliary oil pump to supply a forced quantity of oil for functioning of wet brakes, where oil is received from a transmission housing and returns back to the source, or the wet brakes are an integral part of transmission housing and receive required quantity of oil from the same housing on account of its location. However, the design of an integral construction complicates the serviceability of the wet brakes in the instance of problems. Further, the oil received by the wet brake is not filtered and contain small impurities and particles that lessen the life of the brake due to wear and impregnation

OBJECTS OF THE INVENTION

[0005] An object of the present invention is to propose an improved oil supply system for supply of oil to wet brakes of a tractor and without the requirement of an auxiliary oil pump.

[0006] Another object of this invention is to propose an improved oil supply system for supplying oil to wet brakes and obviates the disadvantages of the known art as described hereinabove.

[0007] Still another object of this invention is to propose an improved oil supply system for supply of filtered oil to wet brakes.

SUMMARY OF THE INVENTION

[0008] In accordance with this invention an improved oil supply system has been provided on the drain line of the hydraulic system which supplies the oil to wet brakes of the tractor. A connection has been provided on the drain line of the hydraulic system which supplies oil to the wet brakes through a passage with a line pressure of average 2-3 kg/cm². Thus this oil supply system positively ensures the oil supply to wet brakes. A hollow bush is so sized and located on the brake housing so as to maintain the required level of oil in the brake housing and to drain the excess oil in the transmission housing. Since the drain line of the hydraulic system already receives the filtered oil, the oil system ensures the supply of filtered oil to wet brakes. Thus the advantage of required amount of filtered oil supply to wet brake as well as ensuing no additional requirement of auxiliary pump are achieved through this invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The invention will be described with reference to the accompanying drawings and wherein:

[0010]FIG. 1. Shows an isometric view of the oil supply system for wet brake of tractor; and

[0011]FIG. 2. Shows a schematic hydraulic circuit of a oil supply system for wet brake of a tractor.

DETAILED DESCRIPTION OF THE INVENTION

[0012]FIG. 1 shows the oil supply system to wet twin brakes located on either side of the tractor. There is a oil filter (1) located inside the transmission housing (11) which acts as an oil tank or reservoir and is connected to pump (3) through suction line (2). Pump (3) supplies oil through delivery line (4) to response body (5), which is further connected to control body (6).

[0013] A brake housing (9) is connected to control body (6) (which is housed in rear cover (12)) through oil tapping line (7) and oil supply, line 8. There is an oil passage from brake housing (9) to transmission housing (11) through hollow bush (10).

[0014] Referring to FIGS. 1 and 2, filtered oil is sucked by the pump (3) from transmission housing through filter (1) and the pressurized oil is then supplied to control body (6). Hydraulic control body (6) can be in three conditions that is neutral, raising and lowering. At neutral condition of control body, port B is open and the oil flows through check valve A and reaches the point (E) as shown in FIG. 2. Depending upon the requirement the drain oil point (E) is partially tapped and is supplied to the wet brakes through hole (F). Balance oil is drained to transmission housing (11) through drain hole (G). During the raising conditions the port (B) and port (C) are closed and oil from the pump goes to hydraulic cylinder (CL) through check valve (H) and port (D), which is turn actuates the hydraulic lift.

[0015] This condition remains for 1-2 seconds. After this immediately the control body comes to the neutral condition, in lowering condition of the hydraulic lift, port (C) opens and oil from hydraulic cylinder (CL) flows through port (C) to transmission housing (11). At this time port (B) is also in open condition and the oil from pump goes to wet brakes as described in neutral condition earlier. Referring to FIG. 1, a hollow bush (10) is provided as connector between transmission housing (11) and the brake housing (9) and the position is to designed that the required minimum level of oil is always maintained in the brake. The excess oil drains back to transmission housing through this bush. 

We claim:
 1. An improved oil system for wet brakes, comprising: an oil filter, suction line, pump, delivery line, response body, control body, oil tapping line, oil supply line, brake housing, hollow bush, transmission housing and rear cover, this oil supply system supplies a required amount of filtered oil without the use of any auxiliary pump to the wet brake where the oil supply has been tapped from the drain of the hydraulic system of tractor.
 2. The oil supply system of claim 1, wherein said oil tapping line (7) has been incorporated in the hydraulic system for the wet brake.
 3. The said oil tapping line (7) of claim 2, is to supply oil to brake housing having a pressure of oil between 2-3 kg/cm².
 4. The oil system of claim 2, wherein the said oil tapping line (7) is so sized that the required amount of oil goes to the wet brakes.
 5. The oil system of claim 1, wherein the oil supply line (8) and oil tapping line (7) is made of either metal or braided flexible pipe.
 6. The oil system of claim 1, wherein the control body (6) is designed with hole (F) and hole (G).
 7. The hole (F) and hole (G) of control body of claim 6 are so designed and sized that the required amount of the oil goes to the wet brakes and remaining oil drains to the transmission housing respectively.
 8. The oil supply system of claim 1, wherein the hollow bush on the brake housing and transmission housing is so sized and positioned so as to maintain the required level of the oil in the brake housing and the excess oil is automatically drained into the transmission housing. 